JP2012168708A - Ic tag - Google Patents

Abstract

An IC tag capable of preventing damage to an IC chip without causing an increase in manufacturing cost.
A circuit substrate, an IC chip mounted on a circuit electrode of the circuit substrate by a flip chip method using a bonding material, and a protective layer provided on a circuit surface of the circuit substrate. 311, a fillet made of a cured body of the bonding material is formed on the periphery of the IC chip 13, and the fillet includes a reinforcing portion that reinforces the IC chip 13, The reinforcing portion covers the side surface of the IC chip 13, and a state where the height dimension along the side surface and the height dimension of the IC chip 13 are substantially equal to each other on the mounting surface of the IC chip 13. The protective layer 311 is formed to include a urethane oligomer and an energy ray curable monomer.
[Selection] Figure 1

Description

  The present invention relates to an IC tag.

Conventionally, non-contact RFID (Radio Frequency Identification) that identifies and manages an article using an IC tag attached to the article is known.
As an IC tag used for such an RFID, a configuration in which an IC chip is mounted on a circuit substrate by a flip chip method is known (for example, see Patent Documents 1 and 2).

By the way, an IC tag is attached to an article by sandwiching an antenna circuit and an IC chip between a pair of flexible films and sheets and using an adhesive one film or sheet.
However, when the IC tag is attached to the outside of the article, for example, when the article is transported, the articles collide with each other, so that the IC chip receives an impact, and the impact causes the IC chip to be damaged. There is.
As a method of preventing such breakage, after mounting an IC chip on an electrode of an antenna circuit using a thermosetting resin, a photocurable resin is applied to the peripheral portion of the IC chip to cure the photocurable resin. Thus, a technique for improving the impact resistance of the IC chip has been proposed (for example, see Patent Document 3).

Also, the IC chip may be damaged when the IC tag is manufactured or bent.
As a method for preventing such damage, one or more kinds of organic peracid compounds and one kind of compounds having at least one polymerizable double bond at the end or side of the molecule are disposed around the IC chip module. A technique of molding with a viscoelastic fluid protective agent mainly composed of the above and at least one plastisol has been proposed (for example, Patent Document 4).

JP 2003-174045 A JP 2003-92312 A JP 2005-33053 A Japanese Patent Application Laid-Open No. 2000-148956

However, in the technique described in Patent Document 3, it is necessary to apply a photo-curing resin to the periphery of the IC chip after mounting the IC chip with a thermosetting resin, and to cure the IC chip. There is a problem that the manufacturing cost rises.
Further, the technique described in Patent Document 4 has a problem that although the IC chip is molded, the impact resistance is not sufficient.

  An object of the present invention is to provide an IC tag that can prevent damage to an IC chip without causing an increase in manufacturing cost.

The gist of the present invention is as follows.
(1) A circuit substrate having a circuit surface on which circuit electrodes are formed, an IC chip mounted on the circuit electrode by a flip chip method using a bonding material, a circuit surface of the circuit substrate, and the circuit surface An IC tag including a protective layer provided on at least one of the opposite surfaces, and a fillet made of a cured body of the bonding material is formed on the periphery of the IC chip, A reinforcing portion for reinforcing the IC chip; the reinforcing portion covers a side surface of the IC chip, and a height dimension of the reinforcing portion along the side surface is substantially equal to a height dimension of the IC chip. The protective layer is formed to include a urethane oligomer and an energy ray curable monomer. The protective layer is formed in a shape extended by a predetermined dimension in a direction along the mounting surface of the IC chip. IC tag, characterized in that.

(2) The IC tag according to (1), wherein the Young's modulus of the protective layer is 2.0 × 10 ⁸ Pa or more and 5.0 × 10 ⁹ Pa or less.
(3) The IC tag according to (1) or (2), wherein a stress relaxation rate after 1 minute when the protective layer is extended by 10% is 50% or more and 100% or less.

  According to the IC tag of the present invention, damage to the IC chip can be prevented without causing an increase in manufacturing cost.

Sectional drawing of the IC tag which concerns on embodiment of this invention. The top view of IC inlet which comprises the IC tag in FIG. FIG. 3 is a cross-sectional view around an IC chip constituting the IC inlet in FIG. 2. FIG. 4 is a plan view of the periphery of the IC chip in FIG. 3. The top view which shows IC inlet in the Example of this invention. Sectional drawing of the IC chip periphery as a comparative example. The perspective view of the roller used in order to evaluate the IC chip in the Example and comparative example of this invention.

  According to the present invention, since the fillet includes the reinforcing portion, even if an external force acts on the IC chip, the impact force can be dispersed and absorbed by the reinforcing portion, and the IC chip can be prevented from being damaged. In addition, since the fillet is formed as a cured body of a bonding material for bonding the IC chip and the circuit electrode, there is no need to use an adhesive separately, and the IC chip can be reinforced and the manufacture of the IC tag. The process is not complicated, and the manufacturing cost is not increased. Furthermore, as a protective layer covering at least one surface of the circuit substrate, a layer containing a urethane-based oligomer and an energy ray curable monomer is applied, so this protective layer can absorb external impact and damage the IC chip. Can be prevented.

In the present invention, the Young's modulus of the protective layer is preferably 2.0 × 10 ⁸ Pa or more and 5.0 × 10 ⁹ Pa or less.
When the Young's modulus of the protective layer is less than 2.0 × 10 ⁸ Pa, the moldability as a film may not be sufficient, and when it exceeds 5.0 × 10 ⁹ Pa, the flexibility is not sufficient, This is because the IC chip may not be broken efficiently because it is easily broken.
Moreover, in this invention, when the said protective layer is extended | stretched 10%, it is preferable that the stress relaxation rate after 1 minute is 50% or more and 100% or less.
This is because if the stress relaxation rate is less than 50%, the shock cannot be effectively absorbed and the IC chip may not be protected from damage.

[Embodiment of the Invention]
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Configuration of IC tag)
As shown in FIG. 1, the IC tag 1 of the present embodiment is a passive IC tag, and has a tag shape obtained by subjecting the IC inlet 10 to predetermined tag processing. The IC tag 1 includes an IC inlet 10, a printing surface sheet 20, a double-sided pressure-sensitive adhesive sheet 31, and a release sheet 32.
The IC inlet 10 includes a flat circuit substrate 11 and an antenna circuit 12 and an IC chip 13 described later formed on the circuit substrate 11.
As the circuit substrate 11, a sheet material such as a synthetic resin film such as polyethylene, polypropylene, polyethylene terephthalate, polyvinyl chloride, polyimide, or polycarbonate, or a paper material such as fine paper, coated paper, glassine paper, or non-woven fabric is used. it can. The thickness dimension of the circuit substrate 11 is not particularly limited and may be appropriately selected depending on the application. For example, the thickness is preferably 5 μm or more and 2000 μm or less, and particularly preferably 10 μm or more and 500 μm or less.

In FIG. 1, the printing surface sheet 20 is bonded to the surface of the circuit substrate 11 opposite to the surface on which the antenna circuit 12 is formed, and protects the IC inlet 10. Visible information such as product information is printed on the top sheet 20 for printing. Examples of visible information of the printing surface sheet 20 include product information (for example, product number and product name), price, barcode, pattern, and mark.
Moreover, as the surface sheet 20 for printing, it is preferable that the surface has printability, The material can apply widely, For example, a synthetic resin film, a synthetic paper, a nonwoven fabric, and paper can be used. Moreover, what formed the to-be-printed layer for performing various printings, such as thermal recording, pressure-sensitive recording, thermal transfer recording, laser beam recording, and inkjet recording, can be used as needed.
Further, the printing surface sheet 20 may be transparent or opaque. Furthermore, a laminate of a plurality of printing surface sheets 20 using, for example, an adhesive such as polyethylene, polypropylene, or polyester, or an adhesive similar to the adhesive listed as the adhesive layer 312 can be used. .

In FIG. 1, the double-sided pressure-sensitive adhesive sheet 31 is laminated on the surface of the circuit substrate 11 on which the antenna circuit 12 is formed.
The double-sided pressure-sensitive adhesive sheet 31 is obtained by applying a pressure-sensitive adhesive to the front and back surfaces of a sheet-like protective layer 311 to form a pressure-sensitive adhesive layer 312 and a patch layer 313.

  The protective layer 311 is formed by energy ray curing of a material containing a urethane oligomer and an energy ray curable monomer.

As the urethane oligomer, for example, a resin composition mainly composed of an energy ray polymerizable urethane acrylate oligomer or a polyene / thiol resin is preferably used.
The urethane acrylate oligomer includes a polyol compound such as a polycarbonate type, a polyester type or a polyether type, and a polyvalent isocyanate compound such as isophorone diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate. An acrylate having a terminal hydroxyl group on a terminal isocyanate urethane prepolymer obtained by reacting narate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane 4,4-diisocyanate, etc. Alternatively, methacrylates such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl acrylate DOO, 2-hydroxybutyl methacrylate, polyethylene glycol acrylate, obtained by further reacting a polyethylene glycol methacrylate.
Such a urethane acrylate oligomer has an energy ray-polymerizable double bond in the molecule and is polymerized and cured by energy ray irradiation to form a film. The urethane acrylate oligomer may be formed by combining a plurality of the aforementioned compounds. The molecular weight of the urethane acrylate oligomer is generally 1000 to 50000, preferably in the range of 2000 to 3000.
Only urethane acrylate oligomers may be difficult to form due to their high viscosity. Further, physical properties such as appropriate flexibility as the protective layer 311 may not be obtained. For this reason, usually, a low-viscosity energy ray-polymerizable monomer is mixed to form a film, which is then cured to form a base film.

The energy ray polymerizable monomer has an energy ray polymerizable double bond in the molecule. As the energy ray polymerizable monomer, an acrylate ester compound having a relatively bulky group is particularly preferably used. This is because, when an acrylic ester compound having a bulky group is used, the stress relaxation property of the protective layer 311 is improved as described later.
Specific examples of energy beam polymerizable monomers for mixing with urethane acrylate oligomers include phenoxyethyl (meth) acrylate, p-cresol ethylene oxide modified (meth) acrylate, o-cresol ethylene oxide modified (meth) acrylate, m-cresol. Aromatic compounds such as ethylene oxide modified (meth) acrylate, phenol ethylene oxide modified (meth) acrylate, benzyl acrylate, isobornyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyloxy Alicyclic compounds such as (meth) acrylate, cyclohexyl (meth) acrylate, adamantane (meth) acrylate, or tetrahydrofurfuryl (Meth) acrylate, morpholine acrylate, heterocyclic compounds such as N- vinyl pyrrolidone or N- vinyl caprolactam. Among these, phenoxyethyl acrylate and p-cresol ethylene oxide modified acrylate are preferable, and p-cresol ethylene oxide modified acrylate is particularly preferable. Moreover, you may use polyfunctional (meth) acrylate as an energy-beam polymerizable monomer as needed. These energy ray polymerizable monomers are preferably 5 parts by weight to 900 parts by weight, more preferably 10 parts by weight to 500 parts by weight, and particularly preferably 30 parts by weight to 200 parts by weight with respect to 100 parts by weight of the urethane acrylate oligomer. Used in proportions.

  The energy beam curable resin may contain a photopolymerization initiator. By containing a photopolymerization initiator, the irradiation amount and irradiation time of energy rays necessary for polymerization and curing can be reduced. Examples of the photopolymerization initiator include benzophenone, acetophenone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, methyl benzoin benzoate, benzoin dimethyl ketal, and 2,4-diethylthioxan. Son, 1-hydroxycyclohexyl phenyl ketone, benzyldiphenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile, benzyl, dibenzyl, diacetyl, 2-chloranthraquinone, or 2,4,6-trimethylbenzoyldiphenylphosphine Examples include oxides. These photopolymerization initiators are preferably used in a proportion of 0.05 to 15 parts by weight, more preferably 0.1 to 10 parts by weight, with respect to 100 parts by weight of the energy beam curable resin.

  In addition, the energy ray curable resin has poor adhesiveness (keying) of the cured film due to volume shrinkage due to curing. For this reason, the energy ray-curable pressure-sensitive adhesive is blended with an adhesion improver for the purpose of improving the adhesion to the substrate. As the adhesion improving agent, a relatively low molecular weight polymer or oligomer such as polyester or urethane can be used.

  The thickness of the protective layer 311 is adjusted according to the performance required for the double-sided pressure-sensitive adhesive sheet 31 and is preferably 20 μm to 500 μm, and particularly preferably 50 μm to 400 μm. As a method for forming the protective layer 311, a liquid resin (resin before curing, resin solution, etc.) is cast into a thin film on a process sheet, for example, and then cured by energy ray irradiation to form a film. .

The Young's modulus of the protective layer 311 is preferably 2.0 × 10 ⁸ Pa or more and 5.0 × 10 ⁹ Pa or less. Further, the stress relaxation rate after 1 minute when the protective layer 311 is extended by 10% is preferably 50% or more and 100% or less.

  The pressure-sensitive adhesive layer 312 is provided on the surface of the protective layer 311 on the antenna circuit 12 side, and seals following the unevenness between the antenna circuit 12 and the mounted IC chip 13. The adhesive layer 312 can be widely applied without any particular limitation as long as the adhesive layer 312 has a sufficient adhesive force that can bond the IC chip 13 and the antenna circuit 12 to the protective layer 311. Silicone-based and polyurethane-based pressure-sensitive adhesives can be used. Among these, acrylic pressure-sensitive adhesives are preferable because they are excellent in terms of adhesive strength.

The patch layer 313 is provided on the surface of the protective layer 311 opposite to the antenna circuit 12 and bonds the IC tag 1 and the product. The patch layer 313 can be widely used as long as the IC tag 1 can be bonded to a product. For example, the same adhesive as the adhesive layer 312 can be used. Although the thickness dimension of the adhesive layer 312 and the patch layer 313 is not specifically limited, For example, 1 micrometer or more and 300 micrometers or less are preferable, and 5 micrometers or more and 150 micrometers or less are still more preferable.
Note that the double-sided pressure-sensitive adhesive sheet 31 may be laminated on the surface of the circuit substrate 11 on which the IC chip 13 is not mounted, or may be laminated on both surfaces of the circuit substrate 11.

  The release sheet 32 is laminated on the adhesive layer 313 on the opposite side of the double-sided pressure-sensitive adhesive sheet 31 from the surface laminated on the antenna circuit 12. The release sheet 32 bears the function of protecting the circuit substrate 11 together with the patch layer 313 in a state before being attached to a product or the like, and if necessary, a release agent layer is provided on the surface in contact with the patch layer 313. It is preferable to provide it. As the release sheet 32, for example, a paper such as polyethylene laminated paper, coated paper, glassine paper, or a synthetic resin film such as polyethylene, polypropylene, or polyethylene terephthalate can be used. Moreover, as a release agent used for the release agent layer of the release sheet 32, for example, a silicone resin, a fluorine resin, or a long chain alkyl resin can be used.

(Configuration of IC inlet)
The IC inlet 10 includes an antenna circuit 12 and an IC chip 13. As shown in FIG. 2, the antenna circuit 12 includes a planar circuit line 121, three connectors 122 </ b> A, 122 </ b> B, and 122 </ b> C, an insulating resist layer 123, and a jumper 124.

The circuit line 121 is formed by being wound a predetermined number of times along the peripheral edge of the circuit substrate 11 and mainly has an antenna function and a power supply function. Note that the number of turns of the circuit line 121 is appropriately determined according to the frequency of the electromagnetic wave to be received and the size of the circuit substrate 11. As a method of forming the circuit line 121, for example, a method of winding a coated copper wire in a loop shape, a method of printing a conductive paste in a loop shape, a conductive metal layer such as copper or aluminum laminated on the circuit substrate 11 is used. A method of forming a loop by etching may be mentioned. The shape of the circuit line 121 is not limited to a loop shape, and is not particularly limited as long as it is a shape that can receive radio waves, such as a linear dipole type.
As the conductive paste, a paste in which metal particles such as gold, silver, nickel and copper are dispersed in a binder or an organic solvent can be used. Examples of the binder include polyester resin, polyurethane resin, epoxy resin, and phenol resin.

  The connection body 122A is formed at the inner end portion of the loop-shaped circuit line 121, and the connection body 122C is formed at the outer end portion of the loop-shaped circuit line 121. The connection body 122B is formed along the outer periphery of the loop-shaped circuit line 121. In addition, the IC chip 13 is disposed between the connection body 122B and the connection body 122C. These connectors 122A, 122B, and 122C are formed in the same manner as the circuit line 121.

The insulating resist layer 123 insulates the jumper 124 and the circuit line 121, and covers the circuit line 121.
As a material for forming the insulating resist layer 123, for example, an insulating resin whose main component is an acrylic resin, a urethane resin, an acrylic urethane resin, or the like can be used.
The jumper 124 electrically connects the connection body 122A and the connection body 122B of the circuit line 121. As the jumper 124, for example, a conductive paste or conductive ink in which metal particles such as gold, silver, and nickel are dispersed can be applied.
Further, as the jumper 124, through holes are provided in the connecting body 122A and the connecting body 122B, and a conductive paste is embedded therein, and the connecting body 122A and the connecting body 122B are connected to the back side of the circuit substrate 11 with a conductive paste or the like. A connected configuration may be applied.

(IC chip connection structure)
As shown in FIGS. 2, 3, and 4, the IC chip 13 includes an IC electrode 131 and is mounted on the circuit electrode 125 using the bonding material 40 by a flip chip method.
Two circuit electrodes 125 are formed in the antenna circuit 12. One circuit electrode 125 is connected to the lead wire 14 extending substantially directly below the IC chip 13 from the connection body 122B, and the other circuit electrode 125 extends approximately directly below the IC chip 13 from the connection body 122C. Connected to the lead wire 14.
In the present embodiment, the IC chip 13 is mounted outside the loop winding of the circuit line 121, but may be mounted inside or in the middle of a plurality of windings. In that case, it is necessary to change the position and the number of the connection bodies as appropriate.

As shown in FIGS. 3 and 4, the IC chip 13 is formed of a plate-like body having a rectangular shape in plan view, and has a mounting surface 132 that faces the circuit electrode 125 and a side surface 133 that is substantially orthogonal to the mounting surface 132.
The IC electrode 131 is formed on the mounting surface 132 of the IC chip 13 and is electrically connected to the circuit electrode 125 by the bonding material 40 via the bumps 134. The bonding material 40 is cured by thermocompression bonding after the IC chip 13 is mounted, and is disposed between the IC chip 13 and the circuit substrate 11 and at the periphery of the IC chip 13. A hardened body of the bonding material 40 arranged on the periphery of the IC chip 13 forms a fillet 41.
As the bonding material 40, for example, solder, anisotropic conductive adhesive (ACA), and anisotropic conductive paste (ACP) can be applied. As this anisotropic conductive adhesive, it is possible to use a material mainly composed of an epoxy resin in which metal particles or the like are dispersed. In this embodiment, a material mainly composed of a thermosetting epoxy resin is used. Used.

The fillet 41 is a cured body of the bonding material 40 that protrudes from the peripheral edge of the IC chip 13. Specifically, as shown in FIG. 3, the fillet 41 is formed in a substantially trapezoidal cross section with the upper bottom portion having a length dimension W <b> 2 and the lower bottom portion having a length dimension W <b> 1 to reinforce the IC chip 13. The reinforcement part 42 for doing is provided.
As shown in FIG. 3, the reinforcing portion 42 is a portion having a rectangular cross section excluding the triangular shape including the inclined portion in the fillet 41 having a substantially trapezoidal cross section, and covers the side surface 133 of the IC chip 13. The reinforcing portion 42 has a predetermined dimension in the direction along the mounting surface 132 of the IC chip 13 when the height dimension along the side surface 133 of the IC chip 13 and the height dimension of the IC chip 13 are substantially equal. (W2) It is formed in an extended shape. That is, the reinforcing part 42 has a reinforcing surface 421 formed so as to extend outward from the upper surface 135 that is the surface opposite to the mounting surface 132 of the IC chip 13. The shape ahead of the reinforcing surface 421 of the fillet 41 is linear, and gradually decreases in height as it goes ahead. In addition, the shape ahead of the reinforcing surface 421 of the fillet 41 is not limited to a linear shape, and may be an arc shape that gradually decreases in height as it goes ahead.

The length dimension (W2) of the reinforcing surface 421 is a distance from the peripheral edge of the IC chip 13 to the peripheral edge of the reinforcing surface 421, and is preferably 50 μm or more and 800 μm or less, particularly preferably 100 μm or more and 600 μm or less. . If the length dimension (W2) is within the specific range, the reinforcing part 42 can disperse and absorb the impact force due to the external force more satisfactorily, and the tact time can be shortened.
The length dimension (W2) as shown in FIG. 3 is the length dimension (W2 ′) or the length dimension (W2 ″) as shown in FIG. 4, and as can be seen from FIG. The length dimension (W2) from the corner of the rectangular IC chip 13 to the peripheral edge of the reinforcing surface 421 is larger than the length dimension (W2 ′) from one side of the IC chip 13 to the peripheral edge of the reinforcing surface 421. ”) Is shorter.

Further, as shown in FIG. 3, the length dimension (W1) from the peripheral edge of the IC chip 13 to the peripheral edge of the fillet 41 is preferably 100 μm or more, more preferably 100 μm or more and 1000 μm or less, and particularly 110 μm or more. 800 μm or less is preferable. The reason is as follows.
That is, when the length dimension (W1) of the fillet 41 is less than 100 μm, the area of the reinforcing portion 42 cannot be sufficiently secured, and thus the periphery of the IC chip 13 may not be sufficiently protected.
On the other hand, when the length dimension (W1) exceeds 1000 μm, the amount of the bonding material 40 is too much, and it takes time to cure the bonding material 40, so that the tact time becomes longer and the productivity may be lowered. . Further, when the heating temperature is raised and the tact time is shortened, the bonding material 40 is suddenly heated and bumps, and voids may be generated inside the fillet 41, so that the strength of the fillet 41 cannot be secured sufficiently, and the IC chip. 13 may not be sufficiently protected.
Further, since the cured bonding material 40 is hard, the flexibility of the IC inlet 10 and further the IC tag 1 may be impaired in the case of a fillet 41 exceeding 1000 μm.

The length dimension (W1) as shown in FIG. 3 is the length dimension (W1 ′) or the length dimension (W1 ″) as shown in FIG. 4. As can be seen from FIG. The length dimension (W1 ″) from the corner of the rectangular IC chip 13 to the peripheral edge of the fillet 41 is longer than the length dimension (W1 ′) from one side of the chip 13 to the peripheral edge of the fillet 41. Shorter.
The planar shape of the fillet 41 may be a perfect circle as shown in FIG. 4, but may vary depending on the shape of the IC chip 13, the shape of the circuit electrode 125, the wettability of the bonding material 40, and the like. Depending on the shape of the fillet 41, the length dimension (W1 ″) from the corner of the rectangular IC chip 13 to the peripheral edge of the fillet 41 is longer than the side of the reinforcing surface 421 from one side of the rectangular IC chip 13. Even in such a case, the length dimension (W1) from the corner of the IC chip 13 to the peripheral edge of the fillet 41 may be shorter than the length (W2 ′) to the peripheral edge. “)” Is preferably 100 μm or more.

(IC chip mounting method)
The IC chip 13 is mounted by a flip chip method. Specifically, a predetermined amount of the bonding material 40 is applied on the circuit electrode 125 of the circuit substrate 11. On the other hand, bumps 134 are provided in advance on the IC chip 13, and the mounting surface 132 with the bumps 134 of the IC chip 13 is pressed against the circuit electrodes 125 of the circuit base material 11 from above the applied bonding material 40, thereby bonding the bonding material. Bumps 134 are inserted into 40. At that time, the bonding material 40 also reaches the periphery of the IC chip 13. Then, the IC chip 13 is heat-pressed for a predetermined time toward the circuit substrate 11 with a flat plate-shaped pressure plate. Here, the pressure plate to be used is made of metal or resin, and has a flat surface area larger than the peripheral fillet of the IC chip 13, and the flat surface portion is subjected to a peeling process so that the bonding material does not adhere thereto. Those are preferred. Thereafter, the fillet 41 is formed on the periphery of the IC chip 13 by curing the bonding material 40. Further, when the IC chip 13 is heat-pressed by the pressure-bonding plate, a reinforcing surface 421 is also formed on the periphery of the IC chip 13.
Examples of the mounting method using the flip chip method include an ESC method, a C4 method, and an ultrasonic flip chip method.

(Effect of embodiment)
According to the IC tag 1 according to the present embodiment, the reinforcing portion 42 includes the reinforcing surface 421 extending a predetermined length dimension (W2) so as to be continuous from the upper surface 135 of the IC chip 13, so that an external force is applied to the IC chip 13. Even if it acts, the impact force can be absorbed by the reinforcing portion 42 and the IC chip 13 can be prevented from being damaged. Further, since the fillet 41 is formed as a cured body of the bonding material 40 for bonding the IC chip 13 and the circuit electrode 125, it is not necessary to use an adhesive separately, and the manufacturing process of the IC chip 13 is complicated. And there is no increase in manufacturing costs. Furthermore, as the double-sided pressure-sensitive adhesive sheet 31 provided in the IC tag 1 according to the present embodiment, the one having the protective layer 311 containing the urethane oligomer and the energy ray curable monomer is applied. It can prevent well.

(Modification of embodiment)
In addition, this invention is not limited to embodiment mentioned above, The deformation | transformation as shown below is also included.
In the embodiment, the IC tag that can be used for the non-contact type RFID is exemplified as the IC tag. However, the IC tag can also be applied as an RFID module. Further, it can be similarly applied to a non-contact IC card or an IC card module.
In this embodiment, a passive IC tag is used, but an active IC tag may be used.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.
Example 1
The IC tag of Example 1 was manufactured by an antenna circuit manufacturing process, an IC inlet manufacturing process, and an IC tag processing process.
(Manufacturing process of antenna circuit)
As shown in FIG. 5, Nikaflex (made by Nikkan Kogyo Co., Ltd. (copper / PET = 35 μm / 50 μm)) which is a copper foil / PET (polyethylene terephthalate) bonded product was used as the circuit substrate 11. An etching resist pattern was printed on the circuit substrate 11 by a screen printing method. Thereafter, unnecessary copper foil was removed by etching, and circuit lines 121 and connecting bodies 122A, 122B, and 122C were produced. Thereafter, an insulating resist layer 123 is formed on the circuit line 121 by using an insulating resist ink (product name: ML25089, manufactured by Japan Atchison Co., Ltd.) in order to couple the connecting body 122A and the connecting body 122B of the circuit line 121. And the jumper 124 was formed on it using the silver paste material (Toyobo Co., Ltd. product name: DW250L-1). A screen printing method was used to form the jumper 124. Thereby, the antenna circuit 12 was produced.

(IC inlet production process)
The IC inlet 10 was produced by mounting an RFID-IC chip 13 (manufactured by NXP Semiconductors, product name: IcodeSLI) on the produced antenna circuit 12 by a flip chip method. For mounting, a flip chip mounting machine (manufactured by Kyushu Matsushita Electric Co., Ltd., product name: FB30T-M) was used. An anisotropic conductive paste (ACP, manufactured by Kyocera Chemical Co., Ltd., product name: TAP0602F) having a coating amount (0.27 mg) 1.5 times the normal amount was used as the bonding material. Then, mounting was performed under the conditions that the heating temperature to the ACP was 220 ° C. in the IC chip 13, the load to the IC chip 13 was 2N (200 gf), and the pressure heating time was 7 seconds.
After mounting, a fillet extending about 338 μm was formed on the periphery of the IC chip 13 by a cured ACP. That is, a fillet having a length dimension (W1 ″) from the corner of the IC chip 13 to the peripheral edge of 338 μm was formed.
This fillet was formed with a reinforcing portion having the same height as the IC chip 13 (160 μm). Further, the reinforcing portion has a reinforcing surface extended from the upper surface of the IC chip 13 by a predetermined dimension in a direction along the upper surface (a direction along the mounting surface of the IC chip). This reinforcing surface has a length dimension (W2 ′) from the peripheral edge of the reinforcing surface to one side of the IC chip 13 of 305 μm, and a length dimension (W2 ″ from the peripheral edge to the corner of the IC chip 13). ) Had a shape of 300 μm.

(IC tag processing process)
On the mounting surface of the IC chip 13 of the IC inlet 10, a protective layer having a thickness of 80 μm containing a urethane oligomer and an energy ray curable monomer, and an adhesive layer and a patch layer formed on the front and back surfaces of the protective layer A double-sided PSA sheet having Specifically, the Young's modulus is 250 MPa as the protective layer, the stress relaxation rate after 1 minute when the protective layer is stretched by 10% is 90.9%, and the loss tangent at 25 ° C. (tan δ = loss) 50 mass parts of urethane-based resin (elastic oligomer having a weight average molecular weight of 5000 (made by Arakawa Chemical)) having an elastic modulus / storage elastic modulus of 0.6 and 10 mass parts of a polyester oligomer as an adhesion improver And 40 parts by mass of phenylhydroxypropyl acrylate as an energy ray curable monomer).
Further, a surface sheet for printing was bonded as a display layer on the surface of the IC inlet 10 where the IC chip 13 was not mounted to process an IC tag. Here, FR4415-50 (manufactured by Lintec Corporation, product name) was used as the top sheet for printing.
In Examples 1 to 4 and Comparative Examples 1 to 5, the Young's modulus, stress relaxation rate, and tan δ of the protective layer were measured by the following methods, and the dimensions of the measurement sample were 4 mm (width). × 15 mm (length).
Here, tan δ indicates how much energy the material absorbs (changes to heat) when the material deforms. The larger the value of tan δ, the more energy is absorbed, and the impact resilience becomes smaller in the shock absorbing test and is less likely to break.
(1) Young's modulus Using a universal tensile testing machine (Autograph AG-10kNIS manufactured by SHIMADZU), a base film cut into 15 mm × 140 mm was installed so that the distance between chucks was 15 mm × 100 mm, and the speed was 200 mm / min. And measured according to JISK-7172.
(2) Stress relaxation rate Using a universal tensile testing machine (Autograph AG-10kNIS manufactured by SHIMADZU), a base film cut to 15 mm x 140 mm was installed so that the chuck spacing was 15 mm x 100 mm, and the speed was 200 mm / It was calculated by (A−B) / A × 100 (%) from the stress A at the time of stretching by 10% and the stress A at the time of 10% stretching and the stress B after 1 minute from the stretching stop.
(3) tan δ
Using an automatic dynamic viscoelasticity measuring device (Leo Vibron DDV-II-EP V-1166 manufactured by Toyo Baldwin Co., Ltd.), from the storage elastic modulus and loss elastic modulus at 23 ° C. at a frequency of 1 Hz, Was calculated.
tan δ = loss elastic modulus E ″ / storage elastic modulus E ′
Five IC tags were produced by the same method. The produced IC tag was checked for operation with Handy RW (manufactured by Welcat, product name: XIT-150-BR).

(Example 2)
Five IC tags were produced under the same conditions as in Example 1 except that the thickness dimension of the protective layer was changed to 105 μm.

(Example 3)
Five IC tags were produced under the same conditions as in Example 1 except that the thickness dimension of the protective layer was changed to 160 μm.

Example 4
Five IC tags were produced under the same conditions as in Example 1 except that the thickness dimension of the protective layer was changed to 300 μm.

(Comparative Example 1)
Five IC tags were produced under the same conditions as in Example 1 except that the amount of ACP (bonding material) applied was changed to a normal amount (0.18 mg). After the mounting, a fillet extending 88 μm was formed on the periphery of the IC chip by the cured ACP. Moreover, as shown in FIG. 6, the height dimension of the fillet 41A is 144 μm smaller than the height dimension (160 μm) of the IC chip 13, and the reinforcing portion was not formed.

(Comparative Example 2)
Five IC tags were produced under the same conditions as in Example 1 except that a protective layer made of PP (polypropylene) (product name: KEP70WA PM 8KX) was used as the double-sided adhesive sheet. did. The protective layer had a thickness of 80 μm, a Young's modulus of 180 MPa, a stress relaxation rate of 36.0%, and a tan δ of 0.2.

(Comparative Example 3)
As the double-sided adhesive sheet, five IC tags were produced under the same conditions as in Example 1 except that the protective layer was made of EMAA (ethylene methacrylic acid copolymer resin (methacrylic acid-containing 20% by weight)). . The protective layer had a thickness of 80 μm, a Young's modulus of 800 MPa, a stress relaxation rate of 49.2%, and a tan δ of 0.3.

(Comparative Example 4)
Five IC tags were produced under the same conditions as in Example 1 except that the double-sided adhesive sheet used was a protective layer made of PEN (polyethylene naphthalate). The protective layer had a thickness of 80 μm, a Young's modulus of 4800 MPa, a stress relaxation rate of 30.0%, and a tan δ of 0.05.

(Comparative Example 5)
Five IC tags were produced under the same conditions as in Example 1 except that a protective layer made of PET (polyethylene terephthalate) was used as the double-sided adhesive sheet. The protective layer had a thickness of 80 μm, a Young's modulus of 5200 MPa, a stress relaxation rate of 25.0%, and a tan δ of 0.01.

  In Table 1, the fillet shape in Examples 1-4 and Comparative Examples 1-5 and the presence or absence of a reinforcement part are shown.

(Evaluation method)
The IC chips of Examples 1 to 4 and Comparative Examples 1 to 5 were evaluated by the following procedures (1) to (3).
(1) As shown in FIG. 5, an IC tag was placed on a stainless steel plate (product name: SUS304, manufactured by Nippon Valtech Co., Ltd.) 50. At this time, the IC tag was placed in a state where the double-sided adhesive sheet of the IC tag faces the stainless steel plate 50.
(2) A roller 60 having a gripping portion 61 as shown in FIG. 7 was placed on the IC tag and rolled. The roller 60 rolled in the roller rolling direction indicated by the arrow in FIG. The roller 60 has a load of 4.45 kg, a cylindrical main body having a diameter of 80.4 mm and a height of 80.4 mm, and a rod-shaped gripping portion 61 having a diameter of 20.0 mm and a length of 100.0 mm at both ends of the main body. It is what you have.
(3) The operation was confirmed with the handy RW every appropriate number of reciprocations, and the IC chip was confirmed for damage.
Table 2 shows the average value of the number of reciprocations in the five IC tags in which the operation of the IC chip could be confirmed as an evaluation result.
In Examples 1 to 4, a reciprocation count of 100 indicates that the test has not been performed more than 100 reciprocations.

Comparing Examples 1 to 4 and Comparative Example 1, in any case, a reinforcing part was formed in the fillet despite applying a urethane-based resin including a urethane-based oligomer and an energy ray-curable monomer as a protective layer. In Examples 1 to 4, it was found that breakage of the IC chip is less likely to occur than in Comparative Example 1 in which the reinforcing portion is not formed.
Further, when Examples 1 to 4 and Comparative Examples 2 to 5 are compared with each other, in Examples 1 to 4 in which a urethane resin is applied as a protective layer in spite of the formation of the reinforcing portion, the urethane type It was found that breakage of the IC chip is less likely to occur than in Comparative Examples 2 to 5 in which a protective layer other than the resin is applied.
From the above, by forming a reinforcing portion that reinforces the IC chip on the fillet and applying a urethane-based oligomer and an energy ray-curable monomer as the protective layer, there is no increase in manufacturing cost and the IC It was confirmed that an IC tag capable of preventing chip breakage could be provided.

DESCRIPTION OF SYMBOLS 1 IC tag 11 Circuit base material 13 IC chip 40 Joining material 41 Fillet 42 Reinforcement part 125 Circuit electrode 132 Mounting surface 133 Side surface 311 Protective layer

Claims (3)

A circuit substrate having a circuit surface on which circuit electrodes are formed;
An IC chip mounted on the circuit electrode by a flip chip method using a bonding material;
An IC tag comprising a circuit layer of the circuit substrate and a protective layer provided on at least one of the surfaces opposite to the circuit surface,
A fillet made of a cured body of the bonding material is formed on the periphery of the IC chip,
The fillet includes a reinforcing portion that reinforces the IC chip,
The reinforcing portion covers the side surface of the IC chip, and a state where the height dimension of the reinforcing portion along the side surface and the height dimension of the IC chip are substantially equal to each other on the mounting surface of the IC chip. It is formed in a shape extended by a predetermined dimension in the direction along,
The said protective layer is comprised including the urethane type oligomer and the energy-beam curable monomer. IC tag characterized by the above-mentioned. 2. The IC tag according to claim 1, wherein a Young's modulus of the protective layer is 2.0 × 10 ⁸ Pa or more and 5.0 × 10 ⁹ Pa or less. The IC tag according to claim 1 or 2, wherein a stress relaxation rate after one minute when the protective layer is extended by 10% is 50% or more and 100% or less.

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